Sounder Transducer Location

[elad]

I am installing a fish finder with an external transducer. Which side of the transom should I install the transducer on, port or starboard, to minimize the affect of prop wash?

[RobS]

I assume you mean transom mounted, not thru-hull. The downward rotation side.

[DougSea]

Not sure which boat you have, and therefore which transmission and prop rotation.

The "rule" though is to have the transducer on the "downward" side of the prop. There are lots of other rules as well. Not too close to chines, not in line with any thru hull fitting. Not behind or in line with a lifting strake. Pretty much not behind anything but smooth hull!

And not mounted too deep. Should have it's face just below the trailing edge of the boat.

[AK_Albin36]

If you want to minimize external wire runs, you may try an in-hull mount. While the Albin hulls are foam cored and quite thick, I've had excellent luck with placing them on centerline, near the bow on my 36 ET. The fiberglass is really thick here, but it must be solid because I'm getting readings down to 1000 feet with a simple 83/50 ducer meant for a transom mount. I like the bow mount as it gives me a bit more reaction time if I'm coming into shallow water. I also have a thru-hull (original Airmar B744), which does slightly better for fish-finding, but overall they are very comparable, usually within a few feet of each other on the bottom.

To test for the best in-hull location, take a 1 gallon ziplock and fill with water. Place the ducer inside and try a few different locations when running to make sure you are getting a good signal. Once satisfied, sand the bottom of the ducer with ~300 grit and the hull with ~80 grit. Using 5-30 minute epoxy (5 min okay for cold water, but use 30 minute if warm water), press the ducer down hard into the hull, then place something heavy on it while it cures. Whatever signal you loose through the hull, you'll get some back with no turbulence.